Figure 4
From: Semiconductor–metal transition in Bi2Se3 caused by impurity doping
(a) Schematic configuration for field-effect measurement, and band diagram at the interface between gate electrode/gate insulator/AgxBi2Se3. The Fermi energy EF of AgxBi2Se3 is assumed to be located immediately above the bottom of BCB. The conduction band minimum of AgxBi2Se3, Ec, under negative and positive Vg is indicated with blue and red lines, respectively. Note that depletion depth xd is much larger than accumulation depth xa. (b) Gate voltage dependence of sheet conductivity of sample #2 at various temperatures. The curves are offset for clarity. The arrows indicate the inflection points. (c) Temperature dependence of field-effect mobility evaluated from Vg < V0 (blue line) and Vg > V0 (red line). (d) Temperature dependence of the inflection point, V0.
